The present invention relates to a new and novel electric discharge machine whereby a work piece can be shaped by the use of rapidly recurring electrical discharges between two electrodes, separated by a dielectric liquid and subject to an electric voltage, and more particularly to a wire electric discharge machine.
One form of a electric discharge machine is known as a wire electric discharge machine often used to cut plates, make tools and dies, utilizes and uses a continuous thin single-strand metal wire held between first and second wire guides and used as an electrode and fed through the work piece. Wire is constantly fed and held between upper and lower guides. The guides move in the x-y plane and the upper guide can typically pivot in one or more axis thereby allowing parts to be cut having a taper or cut into various geometric shapes.
Unfortunately, while many intricate and delicate shapes can be cut using a wire electric discharge machine, certain shapes that require the cutting of thin wall tubing at high precision remain difficult and time consuming. Further, many parts are relatively small and requires an operator to be constantly monitoring the cutting process so that once one part is complete it is removed and a new part is placed in position for processing. This constant monitoring of the process by an operator is relatively expensive and time consuming and also requires close monitoring of the process by a machinist to assure the wheel does not wear or break-down during use and to ensure that process parameters are maintained.
In wire electrical discharge machining operations, the machinist sets a work piece onto a stand such that the work piece is in proper position for cutting. This requires the machinist to precisely place the work piece in position. Failure to properly place the work piece in the proper position will often result in a part being manufacture outside of the specification for the part thus requiring the work piece to be re-cut or scrapped.
Accordingly, a need exists for a electrical discharge machine, and more particularly, a wire electrical discharge machine that can be used to cut intricate and delicate shapes, including cutting shapes involving thin wall tubing, that is relatively inexpensive and time efficient, that does not require the machinist to precisely place the work piece in position for cutting, and that minimizes the need for close monitoring of the cutting process.